Security System Indicator
The security indicator indicates when the Vehicle Theft Security System (VTSS) is arming or is armed. On vehicles equipped with the Sentry Key Immobilizer System (SKIS), the security indicator also indicates the status of the SKIS. This indicator is controlled by a transistor on the IPC circuit board based upon IPC programming, and electronic security indicator request messages the IPC receives from the BCM or the KIN, over the CAN Bus.
The security indicator Light Emitting Diode (LED) is controlled by the IPC logic circuit, and illuminates whenever the IPC receives a battery current input on the fused B(+) circuit. Therefore, the LED can be illuminated regardless of the ignition switch position. The LED only illuminates when it is provided a path to ground by the IPC transistor. Depending on the programming, the indicator can be illuminated solid, flashed at a slow rate (0.5 Hertz, 12.5 percent duty cycle), or flashed at a fast rate (1 Hertz, 50 percent duty cycle). Each time the ignition switch is turned to the ON position the security indicator illuminates for approximately two seconds. The IPC will turn ON the security indicator for the following reasons:
- Security Indicator Lamp-On Message - During the VTSS arming function (approximately 16 seconds), the BCM requests the IPC to flash the security indicator ON and OFF repeatedly at a steady, but fast rate to indicate that the VTSS is in the process of arming. Following a successful VTSS arming, the BCM requests the IPC flash the security indicator ON and OFF continuously at a slower rate indicating that the VTSS is armed. The security indicator continues flashing at the slower rate until the VTSS is disarmed or triggered. If the VTSS has alarmed and rearmed, the BCM will request the IPC flash the security indicator at a steady, slow rate for about 30 seconds after the VTSS is disarmed.
- SKIS Indicator Lamp-On Message - Each time the IPC receives an electronic SKIS indicator lamp-ON message from the BCM, the security indicator will be illuminated. The indicator can be flashed ON and OFF, or illuminated solid, as dictated by the BCM message. The indicator remains illuminated solid or continues to flash until the IPC receives a lamp-OFF message from the BCM, or until the ignition switch is turned to the OFF position, whichever occurs first. For more information on the SKIS and the security indicator control parameters. Refer to OPERATION .
- Communication Error - If the IPC does not receive lamp-ON or lamp-OFF messages from the BCM or the KIN for 10 consecutive message cycles, the security indicator is illuminated by the IPC. The indicator remains illuminated by the IPC until a valid lamp-ON or lamp-OFF message is received from the BCM.
The BCM sends electronic security indicator request messages to control the security indicator when the ignition switch is in the OFF position and the VTSS is arming, armed, or the alarm is activated. When the ignition switch is in the ON or START position, the BCM performs a self-test to decide if the SKIS is operating properly and if a valid key is inserted in the ignition lock cylinder. The BCM then sends the appropriate lamp-ON or lamp-OFF message to the IPC. If the IPC flashes the security indicator upon ignition ON, or illuminates solid after the bulb test, it indicates that a SKIS malfunction has occurred or that the SKIS is inoperative.